1. Field of Invention
The present invention generally pertains to cleaning or clearing devices and methods of using such devices for the in-situ clearing of artificial lumens within a living being including the in-situ clearing of feeding tubes.
2. Description of Related Art
The following is a description of the background of feeding tubes. It should be understood that the device and method of the present invention is not limited to the clearing of feeding tubes but is applicable to a range of artificial lumens such as indwelling catheters  and that feeding tubes are being discussed simply by way of example.
A feeding tube is a medical device used to provide nutrition to patients who cannot obtain nutrition by swallowing. The state of being fed by a feeding tube is called enteral feeding or tube feeding. Placement may be temporary for the treatment of acute conditions or lifelong in the case of chronic disabilities. Varieties of feeding tubes are used in medical practice and are usually made of polyurethane or silicone.
A gastric feeding tube, or “G-tube”, is a tube inserted through a small incision in the abdomen into the stomach and is used for long-term enteral nutrition. The most common type is the percutaneous endoscopic gastrostomy (PEG) tube. Feeding tubes may also be of the nasogastric type commonly called “NG-tube”, which are introduced through the nose, down the esophagus and into the stomach in a procedure called Nasogastric intubation. PEG-tubes on the other hand are placed endoscopically: the patient is sedated, and an endoscope is passed through the mouth and esophagus into the stomach. The position of the endoscope can be visualized on the outside of the patient's abdomen because it contains a powerful light source. A needle is inserted through the abdomen, visualized within the stomach by the endoscope, and a suture passed through the needle is grasped by the endoscope and pulled up through the esophagus. The suture is then tied to the end of the PEG-tube that is to be external, and pulled back down through the esophagus, stomach, and out through the abdominal wall. The tube is kept within the stomach either by a balloon on its tip (which can be inflated or deflated) or by a retention dome which is wider than the tract of the tube. In the case of NG-tubes, once they are passed through the patient's nostril, a clinician must be careful not to accidentally slip the end of the tube into the patient's lungs. Additionally, upon placing the NG-tube in the patient's gastric system, for example the stomach, it is common for the tubes to slip as the primary securing means is to tape the tube to the patient immediately outside the nostril. Clinicians may pass nutrients to the patient's stomach or remove fluids from the patient via the lumen or NG-tube.
Approximately 410,000 PEG-tubes and 5 million NG-tubes are placed each year in the U.S. A down-side of the life-sustaining feeding tube is that they can become clogged. Based on a 35% clogging rate, US civilian medical facilities, treat over 1.7 million NG clogs and 140k PEG clogs annually.
Numerous conditions that may necessitate enteral nutrition over long periods of time include but are not limited to traumatic injury or elderly illness such as Alzheimer's, Parkinson's, or Cancer. When long-term enteral access is needed, gastronomy-(G), jejunostomy-(J) or gastrojejunal-(GJ) tubes are often surgically inserted. J- and GJ-tubes are employed when gastric complications are present and improved nutrient uptake is necessary. Therefore, the J-tube distal end is positioned in the bowels. Reported clogging rates of GJ and J-tubes have been as high as 35% mainly due to the small bore, considerable length, and convoluted geometries of the tubes once placed. As the discussion below suggests, standard nursing protocols to clear tube occlusions are time consuming at best and are often unsuccessful. GJ- and J-tubes are especially challenging due to the curvature associated with placement.
When a patient's enteral feeding tube becomes clogged, the process of clearing it can be time-consuming and expensive, especially if the tube must be replaced. Additionally, a clog can interrupt the patient's supply of nutrients and cause him discomfort. Many nursing policies recommend flushing feeding tubes with water every four to six 5 hours, and before and after administering medications or checking gastric residuals. Even with these policies, the rate of feeding tube occlusion is approximately 12.5%. Small-bore tubes are even more prone to clogging than are large-bore tubes, and clogging of these tubes has been shown to be a major cause of feeding downtime. A patient with an occluded tube may miss several hours of feeding and receiving nutrients before the tube is unclogged or replaced. This concern, along with patients' discomfort and the expense incurred by having to replace tubes that could not be unclogged, identifies problems to be corrected by the present invention.
Over time, feeding tubes become brittle and need to be replaced. A major cause of this is the accumulation of fungus inside the feeding tube. Standard feeding tube maintenance is to “flush” feeding tubes with water; however, this does not remove debris and fungus from the inner walls. Once a tube clogs, it is prone to reclogging.
Medications are the number one reason for tubes getting clogged. Certain medications, such as Metamucil or liquid pain reliever, build up on the inner walls of the tube and promote clogging. Other medications need to be crushed and mixed with water. If these medications are not adequately flushed or crushed finely, they will clog the tube. Older patients receive an average of 8-11 medications regularly throughout the day. Due to medical restrictions on fluid intake, or if the care-giver is rushed, an adequate flush may not occur. A clogged tube can leave an already compromised patient without medication or nutrition for hours, or even days, and is extremely frustrating to both the patient and the caregiver.
Patients with long-term feeding tubes are generally cared for at home or in a long term nursing facility. Advancements in technology and home nursing have allowed the utilization of home enteral nutrition to dramatically increase over the last few decades. While this is certainly positive, the down side is that when a feeding tube becomes clogged such that it cannot be unclogged with conventional methods, the patient must be transported to a specialty hospital to have the tube surgically removed and replaced. For persons recovering in rural areas, this could be even more problematic as an extensive car ride—several hours—may be necessary to reach the specialty hospital. This disruption is a time consuming, expensive, and agonizing experience for the patient and family members. Numerous hours without nutrients and medication could have significant adverse effects on recovery of wounded soldiers, elderly and chronically ill patients.
One product which claims the ability to assist in restoring feeding tubes by degrading the clogged matter is the CLOG ZAPPER™ available through CORPAK® MedSystems of Wheeling, Ill. and is disclosed in part in U.S. Pat. No. 5,424,299 (Monte). This product relies on a chemical solution being injected into an enteral feeding tube to clear remnant food from the tube and decontaminate the tube. The chemical solution mixture comprises maltodextrin, cellulase, alpha-amylose, potassium sorbate, papain, ascorbic acid, disodium phosphate, sodium lauryl sulfate, disodium EDTA, and citric acid. While the solution provides some assistance in degrading the clogged matter, some patients may be allergic to at least one of these ingredients and the system for introducing the chemical solution is not always successful.
The current state of science includes three approaches to remove a clog: (1) syringe flush, (2) chemical and enzymatic treatment, and (3) mechanical devices.
Syringe Flush
The most recommended approach is to use a ‘flushing syringe’. The first step is to insert the syringe into the tube and pull back on the plunger to attempt to dislodge the clog. If not successful, warm water is placed into the tube and pressure, alternating with syringe suction, is performed. This may need to be repeated for up to 30 or more minutes. However, this may not always be done with enough efficiency or regularity and a high percentage of tubes remain clogged.
Chemical and Enzymatic Treatment
Chemical approaches to clog removal involve a nurse flushing the tube with a variety of reported substances, such as enzymes, meat tenderizer, soda, and fruit juices. More recently developed chemical approaches include using a dose of pancrelipase (Viokase®) and sodium bicarbonate mixed with water. The Clog Zapper uses a syringe filled with an unclogging powder with a variety of ingredients. Product directions state to allow the solution to set for an hour before flushing the tube. The InTRO-ReDUCER is a catheter that allows the solution to be introduced directly at the clog site, which has been reported to be more effective than introducing the solution at the external end of the feeding tube. Chemical approaches to clog removal are not effective. Patients can also be allergic to the ingredients in the chemical approaches, or adversely affected by the high sodium content.
Mechanical Devices
Mechanical devices to remove clogs are also available. Tiny brushes on wires can be used to break up the clog, but have been reported to pack the material in some clogs even more densely. The Enteral Feeding Tube DeClogger® by Bionix is a plastic, flexible rod with a spiral tip on the end. The DeClogger can be twisted to break through or pull out obstructions. Even when successful, these approaches can take up to 30 minutes to several hours per patient, do not leave the tube walls clear, and do not progress through tortuous paths well.
What is needed is an apparatus capable of mechanically breaking up the clogged material from the sidewalls and inner portions of indwelling artificial tubes and catheters, and especially enteral feeding tubes. In addition, a regular maintenance schedule is preferred for using the apparatus to clean the walls of the tube. This regular maintenance cleans the tube walls of debris while stopping potential nucleation sites in which new clogs can grow from.
All references cited herein are incorporated herein by reference in their entireties.